The goal of this project is to provide statistical and computational expertise in the design, analysis, and interpretation of experimental and observational studies for a variety of Institute research activities, including both laboratory and human studies. Approximately 80 scientists made use of the Statistical Consulting Service in FY2001. Many of these activities involved NTP's long term rodent carcinogenicity studies. During FY2001 we provided significant input into the preparation of approximately 12 NTP Technical Reports that summarized the results of these studies. We also coauthored a paper in the scientific literature dealing with the carcinogenic effects of magnetic fields. Examples of other collaborations include (i) evaluating the effects of antiretroviral therapy on genetic and morphological endpoints in lymphocytes and sperm of people with HIV infection; (ii) investigating the occurrence of proliferative lesions and reproductive tract tumors in male descendants of mice exposed developmentally to diethylstilbestrol; (iii) evaluating the effects of arsenic, cadmium, chromium, and lead on gene expression regulated by a battery of 13 different promoters in recombinant HepG2 cells; and (iv) designing and implementing a longitudinal study to evaluate the growth and development of uterine fibroids in 300 women of child bearing age.